The present invention relates to a device for centralized interconnection of electric components of a motor vehicle, such as safety fuses, plug-in connectors, wiring harnesses, electronic control devices for electric consuming circuits, switching apparatuses and the like. The connection device is of the type which includes a pack of circuit plates arranged one above the other, each circuit plate including flat conductors and a supporting insulating board for separating conductors at different levels in the pack, a plurality of connector sockets electrically connected to assigned conductors at different levels of the pack to receive corresponding plugs of the electric components.
Known connection devices of this kind (the so-called central electric units) include a pack of circuit boards consisting of flat conductors stamped out from a conductive plate and being separated at different levels of the pack by intermediate insulating plates. The central electric unit performs essentially a distributing function, namely to supply power to different electrical consuming circuits of a motor vehicle, such as for example, lamps, windshield wipers, blinkers and the like and connects the same via strands of conductors or wiring harnesses with a source of electric power. Another function of the central electric unit is to monitor the operativeness of the consuming circuits and to detect and indicate any malfunction. The actuation of respective electrical consuming circuits is effected by means of switching apparatuses arranged on the upper side of the central electric unit. The central electric unit also supports safety fuses for the consumer circuits. The safety fuses are exchangeable and are provided with connector pins which are insertable in corresponding connector sockets on the upper side of the unit; the connector sockets are electrically connected to assigned flat conductors of respective conductor plates in the pack.
The bottom side of the central electric unit is provided with connectors for wiring harnesses of the motor vehicle. The upper side of the unit is also provided with connector sockets for switching apparatuses which usually include an electronic control circuit for actuating a corresponding electric consumer circuit. The switching apparatus usually includes a relay designed such as to perform the desired switching sequence for turning on or off a particular consumer circuit. Since different kinds of electric consumer circuits require different electronic controls, each individual switching apparatus includes a different control circuit. Consequently, the switching apparatuses are relatively expensive inasmuch as apart from the differentiated control circuit they include also additional protective circuits against negative pulses which may occur in the network of the motor vehicle during voltage surges and the like. Accordingly, if a switching apparatus must be replaced due to a defect in a relay, for example, the corresponding electronic controlling and protecting circuits must be discarded or replaced too.
For manufacturing and technological reasons the design and the layout of the flat conductors and connector circuits in the central electric unit is fixed as regards its power distributing function. If it is required to adjust or match the electric central unit to different requirements, this can be done in most cases through relatively large additional expenditures. To change the outlay or configuration of the flat conductors, for example, cost intensive changes in processing tools are necessary and particularly in the case of small series such changes in most cases are prohibitive from economic point of view.